/*
 * Copyright (C) 2012 The Guava Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */

package com.google.common.io;

import static com.google.common.io.SourceSinkFactory.ByteSinkFactory;
import static com.google.common.io.SourceSinkFactory.CharSinkFactory;
import static org.junit.Assert.assertArrayEquals;

import com.google.common.base.Charsets;
import com.google.common.collect.ImmutableList;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.util.Map;
import junit.framework.TestSuite;

/**
 * A generator of {@code TestSuite} instances for testing {@code ByteSink} implementations.
 * Generates tests of a all methods on a {@code ByteSink} given various inputs written to it as well
 * as sub-suites for testing the {@code CharSink} view in the same way.
 *
 * @author Colin Decker
 */
@AndroidIncompatible // Android doesn't understand tests that lack default constructors.
public class ByteSinkTester extends SourceSinkTester<ByteSink, byte[], ByteSinkFactory> {

    private static final ImmutableList<Method> testMethods = getTestMethods(ByteSinkTester.class);

    static TestSuite tests(String name, ByteSinkFactory factory) {
        TestSuite suite = new TestSuite(name);
        for (Map.Entry<String, String> entry : TEST_STRINGS.entrySet()) {
            String desc = entry.getKey();
            TestSuite stringSuite = suiteForString(name, factory, entry.getValue(), desc);
            suite.addTest(stringSuite);
        }
        return suite;
    }

    private static TestSuite suiteForString(String name, ByteSinkFactory factory, String string, String desc) {
        byte[] bytes = string.getBytes(Charsets.UTF_8);
        TestSuite suite = suiteForBytes(name, factory, desc, bytes);
        CharSinkFactory charSinkFactory = SourceSinkFactories.asCharSinkFactory(factory);
        suite.addTest(CharSinkTester.suiteForString(name + ".asCharSink[Charset]", charSinkFactory, string, desc));
        return suite;
    }

    private static TestSuite suiteForBytes(String name, ByteSinkFactory factory, String desc, byte[] bytes) {
        TestSuite suite = new TestSuite(name + " [" + desc + "]");
        for (final Method method : testMethods) {
            suite.addTest(new ByteSinkTester(factory, bytes, name, desc, method));
        }
        return suite;
    }

    private ByteSink sink;

    ByteSinkTester(ByteSinkFactory factory, byte[] data, String suiteName, String caseDesc, Method method) {
        super(factory, data, suiteName, caseDesc, method);
    }

    @Override
    protected void setUp() throws Exception {
        sink = factory.createSink();
    }

    public void testOpenStream() throws IOException {
        OutputStream out = sink.openStream();
        try {
            ByteStreams.copy(new ByteArrayInputStream(data), out);
        } finally {
            out.close();
        }

        assertContainsExpectedBytes();
    }

    public void testOpenBufferedStream() throws IOException {
        OutputStream out = sink.openBufferedStream();
        try {
            ByteStreams.copy(new ByteArrayInputStream(data), out);
        } finally {
            out.close();
        }

        assertContainsExpectedBytes();
    }

    public void testWrite() throws IOException {
        sink.write(data);

        assertContainsExpectedBytes();
    }

    public void testWriteFrom_inputStream() throws IOException {
        sink.writeFrom(new ByteArrayInputStream(data));

        assertContainsExpectedBytes();
    }

    private void assertContainsExpectedBytes() throws IOException {
        assertArrayEquals(expected, factory.getSinkContents());
    }
}
